Homes could soon be acquired by the state government on a voluntary basis as a 2.5-kilometre sky rail is built over Bell Street in Coburg to remove four level crossings from the Upfield train line in Melbourne's north.

The design of the new elevated rail line, which will be up to 11 metres high at some points and stretch from Tinning Street in Brunswick, over Bell Street, to O'Hea Street in Coburg, was released on Sunday.

The state government is opening a "voluntary purchase scheme" to homes that will be most affected by the sky rail.

An artist's impression of the Coburg and Brunswick skyrail.

"This is a very narrow rail corridor, which is why - in part - the elevated rail has been chosen as the best way to remove these level crossings," Transport Infrastructure Minister Jacinta Allan said.

"The Level Crossing Removal Authority will be making contact ... with each individual householder that has been identified [as a] potential candidate for the voluntary purchase scheme.

"We have done this at a number of sites across our level crossing removal program."

She would not reveal on which streets residents would be approached, saying the number of houses acquired would become clearer as people took up offers.

The state government has insisted no houses will be compulsorily acquired and no properties will need to be removed to make way for the sky rail given the nature of the rail corridor.